| 摘要 |
PROBLEM TO BE SOLVED: To keep stable blast furnace operation without worsening a combustibility of pulverized coal and to keep a coke substitution rate, even if the blast furnace is operated in an operation condition in which a pulverized coal ratio is 150 kg/t-p or more.SOLUTION: When an injection amount of pulverized coal per 1 t of molten iron, that is a pulverized coal ratio, is 150 kg/t-p or more, mean volatile matter content of the pulverized coal is 30 mass% or less, and blown air temperature is 1,100°C or lower, stable blast furnace operation can be kept without worsening combustibility of the pulverized coal by injecting at least the pulverized coal and highly combustible reduction materials from a tuyere into a furnace by using two or more lances which can inject at least the pulverized coal and the highly combustible reduction materials, and as a result, a coke substitution rate can be kept. |
